<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
//        var a=12;
//        var b=5;
//        var c='abc';
        var json={a:12,b:5,c:'abc'};
        json.a++;
        alert(json.a);
    </script>
</head>
<body>
<!--json是用来存数据的-->
</body>
</html>